JP2014107480A - Connection method of connection of electronic component and metal wire and inlet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inter-terminal connection method for facilitating alignment while eliminating the tearing of wire when bonding the antenna wire end and the connection bump of an electronic component directly, in the manufacturing process of a non-contact IC card using a winding antenna.SOLUTION: A connection method of the connection of an electronic component and a metal wire includes a step for obtaining a rolling area 3 by flattening the connection part 2 of a metal wire, a step for arranging a conductive member 4 on the rolling area 3, and a step for connecting the connection bump of an electronic component and the rolling area 3 of a metal wire via the conductive member 4.

Description

  The present invention relates to an RFID or non-contact type IC card incorporating an electronic component and a wound antenna, and more particularly to a method for connecting both ends of a wound antenna and a connection terminal of the electronic component.

  As shown in FIG. 3, a non-contact IC card capable of wireless communication has an IC chip 13 mounted on a predetermined portion of an inlet base material 10 having an antenna circuit 11 or a film base material on which an IC chip is mounted. The upper and lower sides of the inserted inlet base material 10 are sandwiched by the overcoat material 12 imparted with design properties. The communication antenna circuit 11 is arranged in a coil (spiral) shape along the peripheral portion of the inlet base 10, and both ends of the coil are led to connection bumps of the IC chip 13. Since the electromotive force of the coil is proportional to the area surrounded by the coil and the number of turns, it is necessary to increase the number of turns of the coil when the usable area is small.

  Coiled antenna circuit is made by patterning metal foil by photolithography, printing with conductive ink such as silver paste, or wrapping insulating fiber or paper around the periphery of the inlet base material. There are several methods such as drawing a metal wire with a diameter of about 30 to 150 μm in a coil shape by using a wiring machine and fixing it with an adhesive. However, a wound antenna is used because of its cost and manufacturing ease. There are also many.

  Since the antenna is laid on the same surface in a coil (spiral) state, both ends of the antenna are placed on the IC chip in order to connect the ends that appear opposite to each other when viewed from the antenna body to the IC chip connection bumps. It is necessary to place them close to the connection bumps. In this case, the photolithographic method and the printing method cross the antenna circuit on the same surface, so lay a jumper part over the antenna circuit or provide a through hole in the inlet base material and pull the coil end to the back surface. Need to be routed. On the other hand, the wound antenna is temporarily insulated and can be easily bent or crossed on the same plane as compared with the former.

  Regarding the connection between the connection bump on the electronic component side mounted in the IC card such as an IC chip and the winding antenna end 2, the connection is stable when the terminals are directly connected as shown in FIG. In some cases, the connection is indirectly made through electrode patterns 16a and 16b whose connection areas and intervals are expanded so as to be surely performed. In the latter case, when an electrode pattern is provided on the inlet base material 10 on which the wound antenna is laid, a relay substrate 15 dedicated to the electrode patterns 16a and 16b is manufactured, and the relay substrate 15 is used as the inlet base material 10. There is a case where it is connected by being fitted into an opening provided in (FIG. 4).

  The connection bump and the antenna wire can be connected by a heat-pressure welding method in which they are pressed and joined while being vibrated using heat and ultrasonic waves, or a method in which a current is generated to generate heat and welding. In any case, it is necessary to separately manufacture the electrode patterns 16a, 16b and the like by the photolithography method, and there is a problem that the merit of using a wound antenna that does not require a photolithography process is lost.

On the other hand, for direct connection, it is necessary to align an antenna wire having a diameter of about 100 μm and a rectangular connection bump having a side of about 100 μm and a thickness of about 50 μm to join the metals together (Patent Document 1). And Patent Document 2). As a bonding method, a metal wire and a minute connection pad of an IC chip are overlapped and pressed while being vibrated using heat and ultrasonic waves and bonded. In order to retain and crimp a thin and easy-to-move metal wire on a minute terminal for a predetermined time, high processing accuracy and technology are required, but there is a problem that the bonding strength is weak and the yield is poor because the bonding area is small.

  Although it is possible to use a modular chip unit without directly connecting the IC chip to the metal wire, there is a problem that the cost is increased and the system is bulky. Moreover, although the edge part of a metal wire can also be extended | stretched, there existed a problem that it was easy to tear at the boundary of the thin part and the circular part, and was weak to external force only by this.

JP 2009-253412 A Japanese Patent No. 3721520 Japanese Patent Laid-Open No. 11-134594

  The present invention has been made in view of the above circumstances in the manufacturing process of a non-contact type IC card using a wound antenna. In direct bonding of the antenna wire end portion and the connection bump of the electronic component, the alignment is performed. An object of the present invention is to provide an inter-terminal connection method that is easy and has no wire breakage.

  The invention according to claim 1 for achieving the above object includes a step of crushing a connecting portion of a metal wire to form a rolled region, a step of arranging a conductive member on the rolled region, and an electronic component And connecting the bumps for connection and the rolled region of the metal wire via a conductive member. This is a method for connecting a connection part of an electronic component and a metal wire.

  The invention according to claim 2 is the method for connecting a connecting portion of an electronic component and a metal wire according to claim 1, wherein the conductive member is an anisotropic conductive member. is there.

  The invention according to claim 3 is characterized in that the electronic component is an IC chip or an IC module, and the connection part between the electronic component and the metal wire according to claim 1 or 2, It is a thing.

  The invention according to claim 4 is characterized in that the metal wire is covered with an insulating layer, and the connection part of the electronic component and the metal wire according to any one of claims 1 to 3 This is the connection method.

  The invention described in claim 5 is an inlet characterized by using the method for connecting a connecting portion of an electronic component and a metal wire according to any one of claims 1 to 4. is there.

  The present invention extends (rolls) a metal wire portion having a substantially circular cross section for connection to a connection bump of an electronic component to expand the area by a factor of 2 to 3, and makes contact with anything. Since the metal wire including the rolled part that is easy to move is fixed with an adhesive conductive member so that it cannot move, there is an effect that the alignment with the connection bump on the electronic component side becomes extremely easy. .

Since the bare IC chip is directly bonded and mounted, it is not necessary to mount a modularized or packaged IC chip, and an inexpensive IC card can be manufactured. In addition, as a result of covering the rolled portion with the resin in the cured conductive member, an effect that the breakage of the metal wire can be suppressed can be expected.

(A)-(d) It is process drawing of the top view explaining the process of connecting the IC chip and metal wire terminal which become this invention. It is a figure of the top view explaining typically a mode that three edge parts of metal wire were put together, and were extended. It is a perspective outline figure explaining composition of an IC card. It is a schematic perspective view explaining the relay substrate and the electrode pattern arrangement on it.

The present invention relates to direct bonding for directly connecting a bump for connection of an IC chip or an electronic component and an end portion of a wire antenna for communication. The direct bonding means that an electrode pattern for expanding the separation distance and expanding the area of the connection bumps of the electronic parts which are fine and have a short separation distance is not used. Although an example in which the electrode pattern is provided on the relay substrate is shown in FIG. 4, it is also possible to form the electrode pattern directly on the inlet without using the relay substrate.
The present invention will be described below with reference to the drawings.

  As shown in FIG. 3, the IC card 1 covers the front and back of the inlet base material 10 on which the antenna circuit 11 and the IC chip 13 are mounted with an overcoat material 12 (plastic base material or paper base material) imparted with design properties. It is molded into a noun size, and the inlet 10 portion is a key component related to the communication function. The inlet 10 may be miniaturized and simply packaged and used as an RFID. Since the antenna has a larger electromotive force as the surrounding area is larger, it is almost always arranged at the edge of the base material regardless of the shape and size of the inlet base material. The IC chip 13 may be simply mounted on the inlet base material 10, or may be accommodated by providing an opening in the inlet 10 by counterbore processing. It doesn't matter.

  As the inlet base material 10, a strip-shaped PET having a thickness of about 20 to 200 μm, polypropylene, polyethylene, polystyrene, nylon, FR-4, or the like is used. In this embodiment, PET is preferable from the viewpoint of cost and strength. .

  The inlet base material 10 is placed on a metal base (not shown), and the metal wire 2 having a diameter of about 30 to 150 μm covered with any of a thin cloth, paper, polyurethane, polyamide, or the like is heated. It lays in a predetermined part using a metal wire laying head with a crimping mechanism (see FIG. 3). As the metal, copper, iron, aluminum, various alloys and clad types can be used, but aluminum that can be easily rolled on PET is preferable. The metal wire can be made to jump over the metal wire and be bent.

  The metal wire can be accommodated in a recess formed in advance along the path to be laid, but hot melt resin is applied to the planned wire laying location on the inlet base, and the metal wire laying head with a thermocompression bonding mechanism It is preferable to use and fix by heat fusion at the same time as laying. After laying a predetermined length, both ends of the metal wire 2 are pulled out to the inside of the loop, and are arranged in parallel with the assumed positions of the bumps for connecting electronic components as shown in FIG. The distance d between the two metal wires 2 is made to coincide with the distance between the bumps for connecting the semiconductor component or the IC chip. However, in the figure, the inlet base material, antenna, IC chip, etc. are all omitted.

Next, the rolling process which makes the edge part of the metal wire 2 flat is performed. Inlet base material 10 is PE
When the metal wire 2 is aluminum at T, the metal wire is laid so as to cross the electronic component mounting position not covered with the hot melt resin and fixed with the hot melt resin. Since the structure is made of metal pedestal / PET / aluminum thin wire, it can be easily crushed and flattened by pressing the aluminum wire with a pressure device having an appropriate head shape (FIG. 1 (b)). The size of the rolling region 3 can be controlled by the size of the contact area of the pressure head. In the case of a copper wire, it is preferable to heat simultaneously with pressurization.

  When the inlet base material 10 is damaged by heating, it is desirable to provide an opening for accommodating the IC chip in the inlet base material 10. In this case, when viewed from above the opening, the inlet is placed on the pedestal so that the end of the metal wire is in contact with the pedestal at the bottom of the opening, and the metal wire is rolled with a rolling member such as SUS from above the opening. What is necessary is just to crush by pressurizing. Or before laying a metal wire, you may carry out by setting the part used as a terminal to the rolling part of the hand press apparatus provided with the rolling part which consists of SUS materials up and down, and restrict | limiting a stroke.

The metal wire is preferably rolled to a sufficient size including a semiconductor chip connection bump (about 50 μ □ for an IC chip). If heat is applied during pressurization, the insulating resin covering the wire can be simultaneously melted and removed. Regarding the method of rolling fine metal wires other than aluminum, either the above hot rolling that rolls above the recrystallization temperature of the metal or cold rolling that rolls at room temperature is possible, but the insulation film is also removed as in this example. The former is preferred when doing so.
In addition, the flat portion is not composed of a single wire, but the entire portion can be rolled in a configuration in which end portions are folded and bundled as shown in FIG. The terminal area becomes large and alignment becomes easy.

  Next, an ACF (Anisotropic Conductive Film) having a predetermined size was attached to the flat portion as the conductive member 4 including the meaning of temporarily fixing the flattened portion on the inlet base material 10 (FIG. 1 (c)). . ACF is obtained by forming a film obtained by dispersing conductive metal particles in a thermosetting resin into a film, and has an adhesive property. The conductive fine particles are fine particles having a diameter of about 3 to 5 μm made of a nickel layer and a gold plating layer from the inside. When pressure is applied while heating with a heater, the conductive fine particles come into contact with each other at the portion where the pressure is applied to form a conductive path and solidify. Due to the development of the conductive path, conduction between the upper and lower terminals can be achieved. In addition to ACF, ACP (Anisotropic Conductive Past) can also be used. The ACF is the same as a tape-like solid, but the ACF only exhibits a fluid paste state. When heat is applied, the resin component is cured and the conductive fine particles are in contact with each other.

  Next, the IC chip is mounted on the ACF (FIG. 1 (d)). The alignment is performed so that the connection bump of the IC chip is directly above the end of the wire that has been subjected to the rolling process via the ACF. The silicon chip and the ACF are heated to a temperature at which the thermosetting resin melts with a heating and pressing device, and then cooled. The same applies to the case where the IC chip is accommodated in the opening. In this way, the connection bump of the IC chip and the flat portion of the metal wire can be connected via the conductive fine particles in the ACF. It is desirable that a coating of Ni (7 μm) / Au (1 μm) is formed on the connection bumps of the IC chip by electrolytic plating, and this is preferable because of low contact resistance with the metal balls on the ACF side. .

  Finally, the inlet 10 is coated from the front and back with an overcoat material (PET-G, PVC, fine paper) using a hot melt resin, or the temperature at which the resin is softened (from 120 ° C.) An IC card can be obtained by die pressing at 150 ° C. and cooling. If the inlet base material and the overcoat material are the same base material, the contact surface by heat melting disappears and an integrated card is obtained. For multi-sided attachment, individual IC cards can be obtained by die cutting.

1. IC card 2, metal wire (antenna wire) end 3, rolling region (metal wire side connection)
4. Conductive member (ACF)
5. Electronic parts (IC chip)
6, jumper section 10, inlet base material 11, antenna circuit 12, overcoat material (plastic, paper, etc.)
13, IC chip 14, overcoat material 15, relay substrate 16, electrode pattern

Claims (5)

Crushing the connecting portion of the metal wire to form a rolling region;
Arranging a conductive member on the rolled region;
Connecting a connection bump of the electronic component and a rolled region of the metal wire through a conductive member, and a method of connecting the connection portion of the electronic component and the metal wire.   The method of connecting a connection part of an electronic component and a metal wire according to claim 1, wherein the conductive member is an anisotropic conductive member.   The method of connecting a connecting portion of an electronic component and a metal wire according to claim 1 or 2, wherein the electronic component is an IC chip or an IC module.   The method for connecting a connection part of an electronic component and a metal wire according to any one of claims 1 to 3, wherein the metal wire is covered with an insulating layer.   An inlet using the method for connecting a connecting portion of an electronic component and a metal wire according to any one of claims 1 to 4.

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